Package org.apache.druid.segment.writeout

Class LazilyAllocatingHeapWriteOutBytes

java.lang.Object

java.io.OutputStream

org.apache.druid.segment.writeout.WriteOutBytes

org.apache.druid.segment.writeout.LazilyAllocatingHeapWriteOutBytes

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable, Channel, WritableByteChannel

public class LazilyAllocatingHeapWriteOutBytes
extends WriteOutBytes

Lazily decides to use a tmpBuffer to act as WriteOutBytes, till more than certain threshold is reached. Once this is met, it switches to delegating all calls to a WriteOutBytes created by delegateSupplier.

This is useful if the data stored in the WriteOutBytes is small enough that buffering the changes in memory would be faster than creating some WriteOutBytes.

Constructor Summary

Constructors

Constructor	Description
LazilyAllocatingHeapWriteOutBytes(Supplier<WriteOutBytes> delegateSupplier, Closer closer)

Method Summary

Modifier and Type	Method	Description
InputStream	asInputStream()	Creates a finite InputStream with the bytes that are written to this WriteOutBytes so far.
boolean	isOpen()
void	readFully(long pos, ByteBuffer buffer)	Reads bytes from the byte sequences, represented by this WriteOutBytes, at the random position, into the given buffer.
long	size()	Returns the number of bytes written to this WriteOutBytes so far.
void	write(byte[] b, int off, int len)
void	write(int b)
int	write(ByteBuffer src)
void	writeInt(int v)	Writes 4 bytes of the given value in big-endian order, i.
void	writeTo(WritableByteChannel channel)	Takes all bytes that are written to this WriteOutBytes so far and writes them into the given channel.

Methods inherited from class org.apache.druid.segment.writeout.WriteOutBytes

close

Methods inherited from class java.io.OutputStream

flush, nullOutputStream, write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

LazilyAllocatingHeapWriteOutBytes

public LazilyAllocatingHeapWriteOutBytes(Supplier<WriteOutBytes> delegateSupplier,
 Closer closer)

Method Details

writeInt

public void writeInt(int v)
              throws IOException

Description copied from class: WriteOutBytes

Writes 4 bytes of the given value in big-endian order, i. e. similar to DataOutput.writeInt(int).

Specified by:

writeInt in class WriteOutBytes

Throws:

IOException

size

public long size()

Description copied from class: WriteOutBytes

Returns the number of bytes written to this WriteOutBytes so far.

Specified by:

size in class WriteOutBytes

writeTo

public void writeTo(WritableByteChannel channel)
             throws IOException

Description copied from class: WriteOutBytes

Takes all bytes that are written to this WriteOutBytes so far and writes them into the given channel.

Specified by:

writeTo in class WriteOutBytes

Throws:

IOException

asInputStream

public InputStream asInputStream()
                          throws IOException

Description copied from class: WriteOutBytes

Creates a finite InputStream with the bytes that are written to this WriteOutBytes so far. The returned InputStream must be closed properly after it's used up.

Specified by:

asInputStream in class WriteOutBytes

Throws:

IOException

readFully

public void readFully(long pos,
 ByteBuffer buffer)
               throws IOException

Description copied from class: WriteOutBytes

Reads bytes from the byte sequences, represented by this WriteOutBytes, at the random position, into the given buffer.

Specified by:

readFully in class WriteOutBytes

Throws:

IOException

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b,
 int off,
 int len)
           throws IOException

Overrides:

write in class WriteOutBytes

Throws:

IOException

write

public int write(ByteBuffer src)
          throws IOException

Throws:

IOException

isOpen

public boolean isOpen()